Nanotubes may be fabricated using a variety of approaches. For example, nanotubes can be produced by conducting chemical vapor deposition (CVD) in such a manner that the nanotubes can be caused to deposit either on a moving belt or cylinder, where the nanotubes consolidate so as to form a non-woven sheet. Alternatively, the nanotubes can be taken up by a spinning device and spun into a yarn. Nanotubes collected as yarns, non-woven sheets, or similar extensible structures can also be fabricated by other means. For instance, the nanotubes can be dispersed in a water surfactant solution, then caused to precipitate onto a filter drum or membrane, where they can be subsequently be dried and removed as a sort of paper. Similarly, nanotubes collected as yarns can also be produced from solutions, and is well know in the art. In general, the nanotubes produced within these extensible structures can be either single-walled (SWNT) or multi-walled (MWNT), and may be made from, for example, carbon, boron, or a combination thereof.
Carbon nanotubes in their solid state are generally produced as agglomerated nanotube bundles. Various methods have been developed to debundle or disentangle carbon nanotubes in solution. For example, carbon nanotubes may be sonicated in presence of a surfactant such as sodium dodecyl sulfate or Triton-X series of polymeric surfactant to be dispersed in a dilute solution that is not adequate for commercial usage. The resulting carbon nanotube dispersion usually contains surfactant or dispersal aid residues that are not removable. Other methods involve the shortening of the carbon nanotubes prior to dispersing the individual nanotubes in dilute solution. Such dilute solution contain a concentration of nanotubes that is generally not adequate for commercial usage
Accordingly, it would be desirable to provide compositions and a process capable of separating nanotubes from their higher morphology order into smaller entities that can be used in carbon nanotubes containing materials.